Country: Republic of MaldivesAt stake: $490 millionOn the Ground: This chain of islands in the Indian Ocean is about three feet above sea level, and scientists fear it could be submerged by 2050. A $63 million buffer built in the 1990s hasn’t solved the problem, so the government is in talks to relocate all 386,000 of its residents to either Sri Lanka, Australia, or India. That would end the Maldives’ tourism industry—more than 600,000 people visit annually—which accounts for 30 percent of the country’s gross domestic product.By the numbers: The Maldives could be completely submerged as early as 2050.